<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>

    <style>

        /* 通配符选择器无序调用即可对全部元素生效 */
        * {

            color: red;

            margin: 0;

            padding: 0;

        }

    </style>
</head>
<body>

    <div class="haha">我是div</div>

    <div class="lv">我是div</div>

    <div class="haha">我是div</div>

    <p>我是p</p>

    <ul>
        <li>我是li</li>

    </ul>

    
</body>
</html>